In the fight against global warming, there is one source of energy with an even greater potential for success than renewables and improvements in energy efficiency, and that is advanced nuclear power.

If we are to stave off the worst effects of climate change, we must confront the problem forcefully -- chiefly with nuclear technologies that can be used to produce base-load electricity in the United States and globally without increasing carbon emissions.

The International Energy Agency has forecast growing demand for energy through mid-century even with more aggressive conservation. Important as renewable energy sources like solar and wind power might seem, they alone can't meet our needs, because they supply power intermittently only when weather conditions permit -- and, moreover, energy storage systems aren't available.

The surest way to tackle the problem is through joint projects with China and other countries to develop and demonstrate advanced reactor systems that are safe and affordable -- and generate electricity even more efficiently than conventional nuclear plants in the United States, which operate on average 90 percent of the time. Recently, high-tech guru Bill Gates went to China for that very purpose.

Gates is chairman of TerraPower, a privately-funded research firm based in Bellevue, outside of Seattle, that has designed a reactor that runs on nuclear "waste," could provide cheap energy and reduce the risk of nuclear-weapons proliferation. Known as a traveling-wave reactor, it uses depleted uranium, a material stockpiled around the world as leftovers from natural uranium after it's been enriched. The reactor uses sodium, not water, for cooling.

TerraPower is working with China, along with Russia, Japan, South Korea and the United States in hopes of building a prototype advanced reactor by 2022 and a commercial reactor by 2025. A number of other start-up nuclear companies as well as large established vendors like Westinghouse and General Atomics are designing advanced reactors for global use in hopes of capitalizing on the huge world market for clean energy. Among the designs now in the works are small modular reactors that run on thorium fuel and molten salt as well as pebble bed and other types of reactors that operate at high temperatures. Additionally, there are designs for small and large advanced reactors that use conventional light-water technology.

China's participation in nuclear-power development is essential, if there is any hope of bringing down greenhouse emissions to safe and practical levels. Its economic growth has come on the back of unparalleled coal use, so it's now in the position of being the world's biggest greenhouse-gas emitter.

Fortunately, China has embraced nuclear power to provide large amounts of non-polluting energy, without detrimental impacts on the climate.The number of nuclear plants under construction in China has grown to 25 and 50 more are planned, in addition to 15 in operation. China's ambitious nuclear-power program is enabling it to shut down scores of coal plants.

The United States can move things along faster in China by continuing to reduce the time it takes for U.S. nuclear companies to obtain export licenses for the sale of reactor components, fuel and expertise. Difficult as it might seem to believe, the U.S. Commerce Department estimates that over the next decade the global market for nuclear technology -- reactor components, fuel and nuclear services -- could reach $740 billion.

It's worth noting that the people who design, operate and maintain U.S. nuclear plants like Vermont Yankee nuclear power plant in Vernon have a great deal of expertise that other countries could use. Requiring U.S.companies to obtain export licenses for their services abroad, as is currently the case, is absurd. Other nuclear countries don't require such licensing, which gives them an advantage in competing for contracts.

A strategy of developing advanced nuclear technologies is one that's getting most attention in a number of other countries, especially those in Asia. In the long run, it is more likely to succeed as an engine of economic growth than the U.S. policy of emphasizing solar and wind energy. The time was never riper for adopting a policy aimed at developing a nuclear reactor using advanced technology and stimulating its production for sale worldwide. It's the sort of thing that could save the planet in the long run.

Bob Leach is a retired radiation protection manager and certified senior reactor operator. He lives in Brattleboro.